Dodge pulled all funding for cars in 01 and the same thing happened. Seat probably wasn't seeing any gains from the vast amount of money thats poured into factory backed teams. IMO why should they. I think Dodge went the right way with providing engineering support for the teams that want it so the manufacturer can focus on doing their job, producing quality cars.
People could say that racing stimulates improvements to design, which is does, but design improvements can only be made so as to fit to the 'rules' which can significantly hamper improvements.
People also could say that running in televised series will boost your sales, I think initially this could be true, but once people know the name this has less of an effect and the money can be better spent targeting their proper audiences most whom don't like racing.
Shame to see them pull out, I doubt they will goto WTCC, but that money can be spent elsewhere with better results IMO.